Porous bent FP channel self-adaptive broadband sound absorption structure

Abstract

The invention discloses a porous bent FP channel self-adaptive broadband sound absorption structure, which comprises a cover plate, a side wall, a bottom plate, a control system and an airtight piston; a plurality of via holes are formed in the cover plate; the cover plate, the side wall and the bottom plate are connected to form a sound absorption back cavity; a plurality of partition plates arearranged in the sound absorption back cavity, and one ends of the partition plates are alternately fixed to the cover plate and the bottom plate. Gaps are formed between the other ends of the partition plates and the bottom plate and between the other ends of the partition plates and the cover plate; the partition plates divide the sound absorption back cavity into a plurality of bent FP channels,the tail end of each bent FP channel is sealed by an airtight piston, and the control system controls the airtight piston to move up and down so as to change the equivalent sound absorption length ofthe bent FP channels. The structure not only can effectively improve the sound absorption capability of the sound absorption structure to low-frequency sound waves and effectively widen the sound absorption bandwidth, but also can detect the working sound waves in real time and quickly adjust the working frequency of the sound absorption structure to achieve a self-adaptive sound absorption effect.

Description

technical field [0001] The invention relates to the technical field of noise control devices, in particular to a porous curved FP channel self-adaptive broadband sound-absorbing structure. Background technique [0002] The use of resonant sound-absorbing structures to reduce the periodic narrow-band noise of major equipment is a current concern and research hotspot. However, the current research on the design of resonant sound-absorbing structures has encountered a bottleneck that needs to be broken through. First of all, the current passive acoustic lining structure mainly plays an effective role in noise reduction for specific frequency bands. Its noise reduction selectivity is strong, and the noise reduction frequency band is too narrow. The noise in the frequency band is sensitive, and the sound absorption effect outside this range drops rapidly, so it lacks flexibility. Even the three-degree-of-freedom acoustic lining structure can effectively absorb the noise frequenc...

AI Technical Summary

Problems solved by technology

At present, acoustic metamaterials have achieved fruitful results in terms of structural design and new physical mechanisms. Sound-absorbing metamaterials with different mechanisms have different characteristics and have their own limitations. The research on acoustic metamaterials with a single mechanism basically focuses on the condensation The exploration of new phenomena in the field of state physics often fails to take into account the comprehensive performance requirements of "low frequency", "broadband" and "intelligent self-adaptation"

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